In a sense, all modern video security surveillance systems (sometimes called closed circuit television, or CCTV) are digital surveillance systems. The images you watch, record, and playback consist of digital video files. Current terminology in the industry differentiates, though, between digital video cameras and analog cameras. Most older systems feature analog cameras that must be connected to a nearby digital video recorder (DVR).
Regardless of the camera’s resolution capability, it’s raw feeds must be transmitted to the DVR, where they are processed into digital video files that can be viewed in real time, recorded, reviewed, and/or copied or stored for posterity. The point is that the conversion of feeds into usable video occurs within the DVR.
In contrast, modern high resolution digital cameras, often designated IP HD, are designed to process raw feeds within the cameras themselves, before sending these digital video files over connecting cables to a nearby network video recorder (NVR), for storage. Although your home or office wireless network can be used to access, view, and control cameras and their feeds, it is presently impractical to install cameras and interface them with your NVR without the use of connecting cables. If nothing else, cables supply your cameras with the power they need to operate reliably.
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